DENVER -- Detroit Mayor Kwame Kilpatrick said he's optimistic that Detroit can conclude deals in the next few weeks to renovate its two worst hulking eyesores, the Book-Cadillac hotel and the abandoned Michigan Central train depot.

He also said he plans to build a strong business case by this summer for a new convention center to replace Cobo Center, with details about location, proposed design and financing to be worked out by next January or February.

In interviews in Denver during a three-day weekend of fact-finding sessions and a management retreat with his cabinet, Kilpatrick said Detroit has much to learn from Denver and other cities that forged city-suburban alliances to build new stadiums, convention centers, housing and cultural attractions.

Kilpatrick wanted his key aides to see and hear how complex, costly deals got done in Denver despite skeptics and city-suburban friction -- deals with challenges similar to those for replacing Cobo or renovating the train depot and Book-Cadillac.

The mayor met Thursday in Detroit with Cleveland-based Ferchill Group, now the expected developer of the Book-Cadillac, the massive but long-vacant hotel structure on Washington Boulevard. "The meeting went well. We believe we can still get it done," Kilpatrick said.

An earlier $147-million agreement with Historic Hospitality, a unit of Kimberly-Clark Corp., to transform the Book into a hotel with 480 rooms and 70 apartments unraveled in January.

To complete the deal, the city and Ferchill need to find a major hotel operator to manage the renovated Book, Kilpatrick said.

The train depot west of downtown is Kilpatrick's preferred site for a new police headquarters, but negotiations between the city and the Moroun family, which owns the Ambassador Bridge and depot, have dragged on for months.

"We'll have final meeting this week with the train station people and our people, and we'll know if we can get done or not. It looks like we can. Hopefully," he said, "we'll have something to announce in the State of the City speech" on Feb. 24.

Both the Book-Cadillac and train depot are extremely difficult renovation projects to pull off in a cost-effective way, because the the buildings are so big, so old, so decayed and vandalized. But Kilpatrick keeps pushing, almost stubbornly so, to make the deals happen because of the symbolic impact they would have.

Kilpatrick had first planned to visit Denver with a small group on a narrow mission, to learn more about how Denver financed its ongoing convention center expansion. But as he learned more from former Denver Mayor Wellington Webb, Kilpatrick decided to expand the trip into a full-blown retreat with 17 of his department heads and top advisers, midway through his first 4-year term.

All day Saturday and Sunday morning, the Detroit group met in closed-door retreat sessions at the Adam's Mark, a downtown hotel created in part by gutting and renovating an abandoned May department store.

Denver, though smaller and demographically different from Detroit, faced some of the same problems over the past 15 years. Its population had shrunk in the 1980s. Its downtown was littered with abandoned stores and empty bank buildings, casualties of the savings and loan crisis.

Since 1988, though, Denver and its six neighboring counties have voted to tax themselves -- mostly through regional sales taxes -- to build museums, baseball and football stadiums, a light-rail system, a convention center and, now, a convention center expansion.

"I wanted a lot of our people to see hear the story of Denver, because they had so many projects going on at once: a strong image enhancement campaign, the participation of the suburban communities in the central city's success and development, and a mayor who took a lot of heat," Kilpatrick said, referring to Webb, who served 12 years as Denver's mayor before leaving office last year.

On Friday, Webb led the Detroit group on a tour of housing, parks, entertainment and convention center projects. An architect, a pollster and several city officials described the financial aspects and political obstacles of reaching regional consensus on issues, a topic all too familiar to the Detroiters.

"What we heard is that when people started believing in Denver, people started walking with a certain swagger after they got stadiums done, and restaurants and loft housing started popping up downtown," Kilpatrick said. "We can do the same thing in Detroit."

Success didn't come quickly or easily to Denver, however. Many projects during Webb's tenure didn't come to fruition until his second and third terms. The current convention center expansion and adjacent convention center hotel, with a combined cost of about $600 million, has been eight years in the making.

A lodging and car rental tax increase was approved narrowly (55-45 percent) by Denver voters in 1999 to fund the Denver convention center expansion, but a plan to put the tax on the ballot in 1997 was scrapped because polling indicated it didn't couldn't win.

"It took a long time to get it on the ballot. It took opinion leaders in the community awhile to get comfortable with it," said Floyd Ciruli, a pollster and consultant who worked on the campaign.

Kilpatrick knows that his plan to build a $1-billion Detroit convention center to replace Cobo Center by 2009 will be a hard sell to suburban counties and to the state Legislature, which must inevitably be part of any financing deal and governing structure.

He said the Denver trip impressed upon the Detroit cabinet that a lot of painstaking and sophisticated political work will be needed to pave the way for a Detroit convention center project.

Kilpatrick said he plans to talk soon with the mayor and convention officials in New Orleans, which is launching a third phase of its convention center expansion. After that, he and Walt Watkins, the city's chief development officer, will meet with the regional Cobo task force -- with suburban and state representatives at the table -- to talk about the political dynamics and making a strong business case to replace Cobo.

"Then we can go to the top political leaders and the business community, the Big Three auto companies, and talk about how to get it done. First, we need to have our data and our business case together, and know exactly what we want," Kilpatrick said.

But while Denver provided some inspiration for Kilpatrick and his team, Detroit's challenges are exponentially greater -- the projects bigger, the political chasms wider.